Timing device



June 23, 1959 F. L. CAMERON 2,891,637

TIMI'NG DEVICE Filed Sept. 27, 1957 Fig.2

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w Frank L. Cumeron ATTORNEY United States Patent THVHNG DEVICE Frank L. Cameron, Liberty Borough, Pa., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application September 27, 1957, Serial No. 686,683 Claims. (Cl. 188--96) This invention relates to timing devices and more particularly to magnetic timing devices.

An object of the invention is to provide a novel timing device which is simple in construction, inexpensive to manufacture and yet effective and efficient in use.

Another object of the invention is to provide a novel timing device, the operation of which is controlled by permanent magnets.

Another object of the invention is to provide a novel timing device in which the flow of fluid is controlled by magnetic means.

Another object of the invention is to provide a novel timing device which is relatively unaffected over a wide range of temperature changes.

Another object of the invention is to provide a novel timing device which retains its timing characteristics over a long period of time.

The invention, both as to structure and operation, together with additional objects and advantages thereof, will be best understood from the following detailed description thereof when read in conjunction with the accompanying drawing.

In said drawing:

Figure 1 is an elevational sectional view of a timing device embodying the principles of the invention, the device being shown during a timing operation.

Fig. 2 is similar to Fig. l but shows the device during a resetting operation.

Fig. 3 is a horizontal sectional view taken on line III-III of Fig. l and looking in the direction indicated by the arrows.

Fig. 4 is a sectional view showing a modification of the device.

Referring to the drawing the timing device comprises a hermetically sealed casing 5 of the non-magnetic material filled with a suitable liquid, preferably, a silicone fluid. Disposed within the casing 5 is a permanent magnet 7 and a check valve 9 of a non-magnetic material having a lower specific gravity than that of the liquid. The magnet 7 is preferably a ceramic magnet but it may be of any suitable type and is of annular or donut shape and is magnetized radially, the outside diameter of the magnet 7 being slightly less than the diameter of the bore of the cylindrical casing 5. Surrounding the casing 5 is an external annular permanent magnet 11 to the opposite sides of which is attached an operating yoke 13. The magnet 11 may also be of a suitable type preferably ceramic and is rectangular in cross section or may be round in cross section as the magnet 7. Attached to the upper end of the casing 5 is a bracket 15 to which a force may be applied or which may serve to fixedly support the casing.

In the normal position, as shown, the valve 9 which is of lower specific gravity than the fluid floats upwardly against the donut magnet 7 and closes the center opening 17 therein.

When a downward force is applied to the yoke 13 drawing the outer magnet 11 therewith, the inner ceramic magnet 7, due to the high density magnetic flux, will move downward therewith. Since the center opening 17 of the donut magnet is closed by the valve 9, the fluid is forced upward between the inner surface of the casing 5 and the outer perimeter of the donut magnet 7 thus providing accurate timing of the movement of the yoke 13 and whatever moving part is attached thereto.

When an upward force is applied to the yoke 13 moving the outer magnet 11 upwardly, the inner magnet 7 moves upward therewith and the pressure of the fluid above the inner magnet 7 forces the valve down (Fig. 2) permitting the flow of fluid through the large center opening 17 When the parts come to rest, the valve 9 floats upward to its seat against the donut magnet.

If an upward motion is to be timed, the yoke 13 can be fixedly mounted and the upward force applied to the bracket 15 to move the casing 5 upwardly. The action, both in operation and resetting, would be the same. If desired moving elements may be connected to both the yoke 13 and the bracket 15 in order to time the separation of the two elements.

If it is desired to use the timer in a position other than vertical, for instance, in a horizontal position, the valve 9 can be made captive by two or more headed retainers 19 as shown in Fig. 4, so that the valve would be closed by the pressure of the fluid.

Having described the invention in accordance with the provisions of the patent statutes, it is to be understood that various changes and modifications may be made in the structural details thereof without departing from the spirit of the invention.

I claim as my invention:

1. A timing device comprising a sealed casing having a fluid therein, an outer permanent magnet surrounding said casing, said casing and said magnet being movable axially relative to each other, an inner permanent magnet disposed in said casing adapted to be held by magnetic attraction substantially in line with said outer magnet upon relative axial movement of said casing and said outer magnet, said inner magnet having an opening therethrough, and valve means adapted to close said opening upon relative axial movement of said casing and said outer magnet in one direction.

2. A timing device comprising a sealed casing having a. fluid silicone therein, an outer permanent magnet surrounding said casing, said casing and said outer permanent magnet being movable axially relative to each other, an inner ceramic permanent magnet adapted to be held by magnetic attraction substantially in line with said outer magnet upon relative axial movement of said casing and said outer magnet, said inner magnet having an opening therethrough, and valve means adapted to close said opening upon relative axial movement of said casing and said outer magnet in one direction to force said fluid through the space between said inner magnet and the inner wall of said casing.

3. A timing device comprising a sealed casing having a fluid silicone therein, an outer permanent magnet surrounding said casing, said casing and said outer permanent magnet being movable relative to each other, an inner ceramic permanent magnet adapted to be held by mag netic attraction substantially in line with said outer magnet upon relative movement of said casing and said outer magnet, said inner magnet having an opening therethrough, and valve means having a lower specific gravity than said fluid adapted to floatingly close said opening upon relative movement of said casing and said outer magnet in one direction to force said fluid through the space between said inner magnet and the inner wall of said casing.

4. A timing device comprising a sealed casing having a fluid silicone therein, an outer permanent magnet surrounding said casing, said casing and said outer permanent magnet being movable longitudinally relative to each other, an inner ceramic permanent magnet magnetized radially and adapted to be held by magnetic attraction substantially in line with said outer magnet upon relative longitudinal movement of said casing and said outer magnet, said inner magnet having an opening therethrough, and valve means adapted to close said opening upon relative longitudinal movement of said casing and said outer magnet in one direction to force said fluid through the space between said inner magnet and the inner wall of said casing.

5. A timing device comprising a hermetically sealed casing having a fluid silicone therein, an outer permanent magnet surrounding said casing, said casing and said outer permanent magnet being movable relatively to each other, an inner ceramic permanent magnet magnetized radially and adapted to be held by magnetic attraction substantially in line with said outer permanent magnet References Cited in the file of this patent UNITED STATES PATENTS 1,278,030 Schmitt Sept. 3, 1918 1,293,697 Canfield Feb. 11, 1919 1,678,555 Cabral July 24, 1928 2,366,562 Schug Jan. 2, 1945 2,536,813 Jones et al. Ian. 2, 1951 2,736,393 OConnor Feb. 28, 1956 

